226 



COIUBEID^. 



two postoculars ; temporals 1 + 1 ; seven upper labials, third and 

 fourth entering the eye; first lower labial in contact with its 

 fellow behind the symphysial ; four lower labials in contact with 

 the anterior chin-shields, which are longer than the posterior. 

 Scales in 15 rows. Ventrals 111; anal divided. Pale brown 

 above, speckled with darker; head and nape darker; whitish 

 beneath. 



Total length 140 millim. 



British Honduras. 



«. c? (V. Ill ; C. P). British Honduras 0. Salvin, Esq. [P.]. 



20. Homalocraninm atriceps. 



Homalocranium atriceps, Giinth. Biol. C-Am., Rept, p. 146, pi. lii. 

 fig. B (1895). 



Eye not half as long as the snont. Eostral broader than deep, 

 well visible from above ; internasals half as long as the praefrontals ; 

 frontal hexagonal, obtuse-angled in front, acute-angled behind, once 

 and one third to once and a half as long as broad, longer than its 

 distance from the end of the snout, shorter than the parietals ; 

 nostril between two nasals, the posterior in contact with or 

 narrowly separated from the prseocular ; two postoculars ; temporals 

 1-|-1; seven upper labials, third and fourth entering the eye; 

 first lower labial in contact with its fellow behind the symphysial ; 

 four lower labials in contact with the anterior chin-shields, which 

 are longer than the posterior. Scales in 15 rows. Ventrals 123- 

 125 ; anal divided ; subcaudals 55-59. Pale reddish brown above ; 

 upper surface of head blackish, bordered behind by a whitish cross- 

 bar ; lower parts white. 



Total length 170 millim. ; tail 47. 



North Mexico. 



a-b. c? (V. 123, 125 ; 0. 65, 59). Nuevo Leon, W. Taylor, Esq. [P.]. 



(Types.) 



21. Homalocraniuiu planiceps. 



Coluber planiceps, Blcdnv. Nbuv. Ann. Mus. iv. 1835, p. 294, pi. xxvii, 



fig. 3. 

 Homalocranium planiceps, Dum. 8^ Bibr. vii. p. 857 (1854) ; Jan, 



Arch. Zool. Anat. Phys. ii. 1862, p. 51, and Icon. GSn. 15, pi. ii. 



fig. 2 (1866) ; Bocourt, Miss. Se. Mex., Rept. p. 581, pi. xxxvi. 



fig. 7 (1883) ; Gunth. Biol. C.-Am., Bept. p. 145 (1895). 

 Tantilla nigriceps, Kennicott, Proe. Ac. Philad. 1860, p. 328 ; Cope, 



Proc. U.S. Nat. Mus. xiv. 1891, p. 598._ 

 Scolecophis fumiceps, Cope, Proc. Ac. Philad. 1860, p. 871. 

 Tantilla planiceps. Cope, Proc. Ac. Philad. 1861, p. 74, and Proc. 



U.S. Nat. Mus. xiv. 1891, p. 697. 

 Homalocranium prseoculum, Bocourt, Miss. Sc. Mex., Rept. p. 582, 



pi. xxxvi. fig. 8. 



Eye not half as long as the snout, which is much depressed and 



